1. Technical Field
The present invention relates to a connecting structure for connecting a screw-down type connector to an electrical connection box or the like.
2. Description of the Related Art
Generally speaking, when it is required to either connect the electrical connection box to a battery power source or connect a connector for large current to another connector for large current, the above screw-down type connector in which a connector terminal is connected to another terminal through the intermediary of a terminal connection bolt, has been used in order to realize a certain electrical connecting condition therebetween.
As a typical conventional connecting structure for inserting and fitting such screw-down type connector into the electrical connection box, there is known a structure which is composed of a fusible link connector as the screw-down type connector and an electrical connection box into which the fusible link connector is to be inserted.
In the above connecting structure, the fusible link (FL) connector consists of a fusible link, an insulating housing for accommodating the fusible link and a pair of nuts to be inserted into nut-fitting portions provided in the insulating housing.
On the other hand, the electrical connection box is provided with a connector receiving portion into which the FL connector is inserted and fixed thereto. The connector receiving portion consists of an inlet shaped so as to accord with a profile of the insulating housing, an inside wall extending from the inlet downwardly, a plurality of guide grooves formed in the inside wall up and down, a pair of flexible engagement pawls projecting inwardly at the inlet, a housing-abutting part projecting from the inside wall and an opening which opens below the FL connector for radiating heat generated therefrom.
The insulating housing further includes one insert guide formed on a side wall where the nut-fitting portion is not provided and two insert guides formed on the opposite side wall where the nut-fitting portion is not also provided.
In assembly, these guides of the insulating housing are inserted into the guide grooves of the connector receiving portion so as to slide therein while the engagement pawls are engaged with engagement projections formed on the insulating housing. Then, abutting on a lower end of an intermediate wall of the insulating connector, the housing-abutting part serves to restrict a limit of the inserted insulating housing to a predetermined regular position. The housing-abutting part is formed along the lower end of the intermediate wall so as not to close the opening for heat-radiation.
In order to fit the FL connector in the connector receiving portion of the electrical connection box, the lower end of the insulating housing is inserted into the inlet while aligning the guides of the housing with the guide grooves, respectively. With the above insertion of the insulating housing, it can be shifted along the guide grooves downwardly. At the same time when the intermediate wall of the insulating housing comes into contact with the housing-abutting part, the engagement projections engage with the engagement pawls, so that the FL connector can be fitted into the electrical connection box. Under such a condition, an upper end of the insulating housing is positioned in level with an upper surface of the electrical connection box.
In the above-mentioned conventional connecting structure, however, there exists a possibility that even if at least one of the nuts is not inserted up to the predetermined utmost position in the insulating housing, the FL connector can be fitted to the regular position in the connector receiving portion as similar to a case that the nuts are inserted up to the utmost positions. Such an incomplete fitting of the nut would be detected by an operator at the opportunity of tightening a terminal connection bolt to the nut in process of connecting plate terminals of wire harness to fuse terminals of the FL connector. In this case, upon removing the FL connector from the connector receiving portion, the operator has to insert the nut completely, so that the operation will be complicated. Particularly, in case that the nuts are press-fitted in the FL connector, the operator has to fit the nuts again by using a fitting tool. Therefore, such an operation may cause a reduction of the workability in connecting the plate terminals.